a emulator is a programme wich copies an exact replica of somthing els. on a big screen not a small tiny screen of a game boy advance.for example on this website there are n64 emulators and gba emulators.wich means gba emulator copies a real game boy advance with addtional options.so you can launch a emulator game(rom) and it plays exactly as you whould play the game on a real game boy advance.and you can even do much more on the emulator than you can do on the real thing.you can increase/decrease game play speed , you can skip frames , you can make the graphics better , you can play it on a big screen , and meany other options but the best thing it is totally free.
